We had the perfect demo sled last season to test TeamFAST’s new Tri-Tek Assault Airshock system: a 2010 Ski-Doo GSX LE. Powered by the E-TEC 600 H.O. engine, it’s a quick, lightweight solo cruiser that can handle an aggressive pace when the rider wicks it up.
Assault shocks are designed for high-mile tourers (like a GSX rider), but they have the flexibility to handle rugged damping duties required by aggressive riders, too. Assault Airshocks are unlike all other snowmobile shocks that use air as the spring. The air chamber is a rolling membrane – it feels like rubber, but it’s not – rather than a rigid metal cavity. Not only does it look different, but the membrane has more than twice the air capacity of traditional snowmobile air shocks and it provides a suppler ride.
Small changes in air pressure made a significant difference in ride quality. We started with the three dampers — ski shocks, front-track shock — set to 40 psi, as recommended by TeamFAST. This gave our GSX a sportier feel than it had in stock form and we were able to hit bumps at faster speeds, but the suspension was too firm and the sled was tippy through turns. Reducing the shocks to 38 psi with a Fox Racing Shox hand pump made the suspension more compliant and more comfortable, but the machine still suffered from inside ski lift.
More miles on the shocks revealed differences between the Tri-Tek system and the stock suspension. We were feeling more kick from the stock rear track shock now, so much that we almost did a headlight check off of a 1-foot kicker. This might have been because the TeamFAST shocks enabled us to hit stuff harder while the rear shock was being over-worked.
We reduced ski shock pressure to 36 psi, and then to 32 psi. This reduced ski lift, but not until we also lowered the front track shock to 32 psi did we really start to notice an improvement in overall control. For the rest of the season we experimented with air pressure settings until we got the ride quality and handling dialed in.
Our ultimate setup proved to be with the IFS shocks set to 33 psi and the front skidframe shock down to 25 psi. The sled could be pushed hard into a corner with confidence and powered out with minimal ski lift. Our GSX was comfortable and it exhibited its best control while still able to handle big bumps and deep holes with control and a smooth stroke through the suspension travel. Our final setting for the front track shock was 15 pounds less than TeamFAST’s starting point, but that’s where the sled felt the most stable and planted.
With stock shocks installed and the suspension unloaded, the bottom of the front bumper was 18-1/2 inches off the ground; the bottom of rear bumper was at 20-3/4 inches. With the Tri-Tek installed and set to our final air pressures, the bottom of the front bumper was 20 inches from the ground; bottom of the rear bumper was 20-9/16 inches from the ground. The footwell measured about one-quarter of an inch farther from the ground with the Assault system installed.
A tradeoff we’ve felt with other air shocks was increased body roll compared to what a coil-over shock would allow, but the Assault resisted roll-over through hard turns and that helped our Ski-Doo maintain its ability to carve the trail. The Tri-Tek system made our Ski-Doo GSX feel tighter and more precise than it did with the stock Motion Control shocks.
Another advantage is their tunability and how remarkably sensitive they are to adjustments. Granted, once a person gets them dialed-in the rider won’t likely change the settings, but a snowmobiler can tune his or her suspension through trial and error with a small hand pump. The stock rear shock was the weak link in this setup; fortunately TeamFAST offers an Assault shock for the rear this season.
Installation was downright frustrating. It was supposed to be as simple as removing and reinstalling six bolts, but the shock eyelet bushings were too thin for the A-arm mount tabs. Plus, a nosepan rivet prevented each Assault shock’s eyelet from reaching its respective upper mount holes in the shock towers.
TeamFAST promptly sent thicker bushings and said to use an electric rotary tool to grind the rivet head for more clearance, and if that wasn’t enough we should also remove material from the shock eyelet for more clearance. With new bushings and the eyelet “re-shaped” by our Dremel tool, the front shocks fit. The front track shock’s upper bushings were too wide, so we brought out a grinder, reduced their thickness and finished the installation.
Fortunately, Assault Airshocks redeemed themselves after we got them out of our shop. They’re quality, intricately designed dampers that we’d endorse for any snowmobiler who wants more comfort and control for long rides, aggressive rides or anything in between. Assault Airshocks are available for Arctic Cat, Polaris, Ski-Doo and Yamaha sleds. The three-shock Tri-Tek kit retails for $1,190.